Meet the REXUS team: HARTS

HARTS is the first Slovak team to participate in the REXUS/BEXUS Programme, representing the Technical University of Košice. The project focuses on developing a thermal protection system to enhance spacecraft safety and reusability during atmospheric re-entry. When spacecraft return to Earth, they experience intense friction with the atmosphere, generating extremely high temperatures that can damage their structures and internal systems. Existing thermal protection typically relies on ablative shields, protective layers that burn away to dissipate heat but cannot be reused.

The HARTS experiment addresses this issue through a hybrid thermal protection concept. By combining an ablative shield with an active helium-based cooling system, the design leverages the advantages of both passive and active thermal protection methods. The outer ablative layer effectively handles the initial high heat load by gradually burning away, while internal channels within the shield carry helium gas to actively remove additional heat. This helium, left over from pressurizing rocket fuel tanks, is released when peak heating occurs, absorbing and dissipating thermal energy.

To evaluate this hybrid system under realistic conditions, the experiment deploys the thermal shield on an experimental capsule designed specifically for re-entry tests. After release from the REXUS rocket, the capsule falls through the atmosphere; onboard sensors detect the rising temperature and activate the helium cooling channels. Continuous real-time data enable assessment of how effectively the system manages extreme thermal loads. At lower altitudes, a parachute system safely recovers the capsule, allowing detailed inspection of the shield and retrieval of data.
The team consists of 13 students from the Technical University of Košice: four from the Faculty of Aeronautics, six from the Faculty of Mechanical Engineering, and three from the Faculty of Electrical Engineering and Informatics. The collective goal of HARTS is to demonstrate a practical approach toward safer, more efficient, and reusable thermal protection systems, thereby advancing technologies essential for future space missions.

HARTS experiment in a nutshell